I just completed The Reason for God by Tim Keller, Pastor of Redeemer Presbyterian Church in New York City. I have nothing but high praise for the book. I hope to use it as a major resource for a sermon series in the future.
The approach of the book is apologetic. Keller seeks to undermine the major objections and arguments that are often used by skeptics today.
This is a really helpful resource to put into the hands of any friends or family who object to Christianity on differnent grounds. Additionally, it would be helpful for Christians to read this and familiarize themselves with much of the reasoning Keller uses to answer skeptics’ questions.
You can find some online audio resources here where Keller answers difficult questions.